Die removing device



Jan. 7, 1947. A..BOLDUC DIE REMOVING DEVICE Filed Jan. 25, 1945 I INVENTOR. 4 flZ}e/*Z ,Balizzc.

BY W atively movable parts of a machine.

Patented Jan. 7, 1947 UNITED STATES PATENT OFFICE DIE REMOVING DEVICE Albert Bolduc, Detroit, Mich.

Application January 25, 1945, Serial No; 574,589

9 Claims.

The invention relates generally to dies adapted to cooperate with punches for perforating sheet metal or the like, and it has particular relation to a device for removing the dies from holders therefor.

In certain respects, the invention is related to and constitutes an improvement over the invention in my copending application for patent, Serial No. 544,792, filed July 13, 1944.

As stated in the copending application for patent, it is conventional to use a die element and a punch which are, respectively, anchored on rel- The die is held in an opening in a holding plate or member and perhaps usually is press fitted in the opening in order to positively resist displacement durin use of the machine. In some instances, the die may be releasably held in the opening by means of a spring-pressed ball in the holder which is adapted to seat in a groove or recess in the die. The copending application for patent is concerned with a device for pulling the die outof the opening without removing the holder from the machine, and generally includes a shank insertable into the die opening and provided with expandable means for engaging the die in order to remove it upon a reverse movement of the shank.

One object of the present invention is to provide an improved device for removing the die while leaving the holder in place on the machine wherein an improved expandable means is provided on the shank for engaging the die.

Another object of the invention is to provide improvements in a device for this purpose which includes means for releasing the spring pressed ball or other locking device at the same time that the shank is inserted into the die opening.

Other objects of the invention will become apparent from the following specification, from the drawing relating thereto, and from the claims hereinafter set forth.

For a better understanding of the invention, reference may be had to the drawing wherein:

Figure 1 is a vertical View, partly in cross section, illustrating an apparatus according to one form of the invention;

Fig. 2 is a cross-sectional view taken substantially along the line 22 of Fig. 1;

Fig. 3 is a cross-sectional View illustrating a different form of the invention which particularly is adapted to removing a die having a tapered openin .Fig. 4 is a similar cross-sectional View illustrating another form of the invention adapted also to remove a die having a tapered opening; and

Fig. 5 is a cross-sectional view illustrating a hand. device for removing dies held inholders by a spring-pressed locking element.

Referring to Fig. 1, the mechanism illustrated comprises an upper platen it] having a unch holder or block it secured byscrews l2 to the platen. The block or holding member H has an opening 14 adapted to receive a punch (not shown) and for releasably holding the punch in position a spring-pressed ball device is employed. This device comprises a ball I5 movable in a bore it in the block and which normally is urged towards the opening 14 by a spring ii. The ball normallyengages agroove or recess in the punch and upon upward movement of the latter, the ball through a wedging action prevents the punch from being pulled out of the opening. To enable pushing the ball upwardly when the punch is to be removed, a small opening I9 is provided at the lower end of the bore Hi, and by pushing a pin or other suitable instrument upwardly through. the opening IS, the ball maybe lifted away from the punch so as to permit withdrawal of the latter.

The lower part of the mechanism comprises a base 20 having a block 2! r'eleasably fastened thereto by devices '22. 'On the upper side of this block, a die holder 23 is fastened by screws 24 and this holder has an openin 26 for receiving a die '21. In the structure shown, the die *2! is sufficiently press fitted into the opening 26 that normally it will not be removed by any forces occurring during operation of the machine, and consequently if the die is to be removed or replaced, considerable force is required to eiiect such removal. It is to be noted that the die has an opening 28 through which the punch operates and that below this opening a larger diameter 29 is provided. At the junction of the two diameters, a slightly rounded annular shoulder 36 is present.

The present invention comprises shank means indicated generally at 3!, which includes an element 32 having a lower tubular portion 33 and a solid upper end portion 34 disposed in the open ing 14. The outer peripheral surface of this solid end portion hasa groove or recess 35 adapted to receive the ball F5 in order to hold the shank means in the opening 14, and the relation between the shank means, spring-pressed ball, and holder H is substantially the same as between the normally used punch, spring-pressed ball, and holder. In other words, by lifting the ball, the shank means 31 can be readily substituted for the punch. Asecond recess or groove 31 is shown which adapts the shank means for use in connection with another type of punch holding means.

A second part of the device comprises a pin 38 which has it upper end threaded into the threaded upper end of the tubular portion 33 as indicated at 4i]. It might be observed at this time that the upper end of the opening in the tubular portion 33 does not generally extend past the groove 35 so that the shank means 32 has a solid resistance to any crushing forces which might be applied against the shank by the ball due to the wedging action mentioned. At its lower end, the pin 33 ha a frusto-conical head 43 and the larger diameter of the head is slightly smaller than the diameter of the die opening 28 so that the pin can readily move downwardly through the die opening. It will be noted that the lower end of the tubular portion 33 terminates substantially above the frusto-conical head 43 so as to provide an annular shoulder 44.

The tapered wall of the head 43 and the shoulder 44 provide a recess or groove at the lower end of the pin 38 and in this space a split ring 41 is provided. Thi ring has a conical inner surface 48 which may substantially fit the head 43 and this inner surface of the ring joins at its upper end a cylindrical inner surface 49. The outer surface of the ring is also frusto-conical, as illustrated at 50, but the slope is opposite to the surface 48. At its larger and upper end, the surface 50 joins an annular shoulder 5i extending radially inwardly on the ring and at the inner edge of this shoulder, the ring has a cylindrical wall 52. The split in the ring is indicated at 54 in Fig. 2.

With the parts assembled and the shank mean-s 3i carrying the ring 4! disposed above the die 21, the ring is free to move axially between'the surface 48 and the shoulder 44 and to contract in dimensions when moved upwardly towards the shoulder. When the platen I is moved downwardly, the head 43 on the pin 38 enters the die opening 28 and the smaller end of surface 50 on the ring strikes the edge of the opening and movement of the ring is interrupted. Continued movement of the shank means downwardly causes the shoulder 44 on the shank means to engage the upper endof the ring and to force it through the die opening and during this movement the ring contracts as the tapered surface 50 moves through the die opening. It should be understood that the dimensions are such that the ring can pass through the die opening through its resilient contracting and that the size of the split 54 and dimensions of the ring and pin 36 are such as to permit sufficient contraction of the ring so as to allow its movement through the die opening.

As soon as the larger end of the surface 50 passes the lower end of the die opening 28, the inherent resiliency of the ring expands it so as to move the shoulder under the shoulder 30. Now, upon reverse movement of the platen, the engagement of the shoulders stops the ring from moving and the head 43 forcefully expands the ring against the wall of the die with the shoulder 51 under the shoulder 30. Continued movement of the platen upwardly, after the ring has expanded as much as it can, will cause the ring and die to move with the pin and hence, to be moved out of the opening 26. After the die is thus removed, the pin can be removed from the tubular shank member 33 by unthreading it and 4 in this manner the die can be separated from the shank means.

In the construction shown by Fig. 3, a die 60 is shown having a, gradually tapering inner surface 61 and in this case the ring 4'! is moved entirely through the die opening to engage under its lower surface as indicated at 62. Upon upward movement of the platen, this engagement will remove the die substantially in the same manner as previously mentioned. The shank means in this case comprises a sleeve 63 on a pin 64 and the pin has a reduced threaded upper end 65 which is threaded into a holder G5. In general, operation of the device shown in Fig. 3 is the same as that shown in Fig. 1.

In the structure shown by Fig. 4, the same die is illustrated, but in this case instead of engaging the die by shoulders, a ring 66 is employed which has an outer conical surface 61 adapted to be forced against the tapered die opening. The inner surface of the ring is tapered substantially to fit the tapered end of the pin 64 and it aZso will be noted that the lower end of the ring has a frusto-conical outer surface 19 adapted to act as a piloting surface when the ring is moved downwardly through the die opening. Hence, generally, the ring in thi case is diiferent from that shown in Fig. 1 in that the outer surface of the ring not only has a piloting frusto-conical surface, but it also has a reversely directed surface 61' adapted to be wedged tightly against the die. The wedging relation between the parts as the shank is pulled upwardly locks the die to the.

shank and in this manner it is removed.

In the construction shown by Fig. 5, the die is held in a holder H by means of a spring-pressed ball 12 on the order of that provided in Fig. 1 for the punch. The die indicated at 13 has a groove or notch 14 for receiving the ball 12 and the ball may be pressed downwardly to release the die by inserting a pin through an access opening in the holder H. The die otherwise may be the same as that shown in Fig. 1. The shank means includes a pin 16 and sleeve 71 on the order of those shown in Fig. 3, but the pin in this case is threaded into a hand-holding element 18. This hand-holding element at one side of the pin 16 has a threaded opening E9 in which a plug 8| is threaded and the plug has an opening 82 extending vertically in offset or eccentric relation to the axis of the plug. This opening receives a plunger 84 having a lower end adapted to enter the opening 15 and press the ball 12 downwardly and the upper end of the plunger 84 has a knob 85 by means of. which the plunger may be pressed downwardly.

It should be evident that if the hand-holding element 18 is pressed downwardly so as to move the pin and ring through the die opening, the pin 84 can at the same time be moved into the open ing 15 so as to press the ball 12. When the pin 84 has been moved to release the die, reverse upward movement of the hand device locks it to the die so as to pull it from the opening. It might be mentioned that in such cases where the die is held by a spring pressed ball, the die will have a close fit with the opening of the holder, but ordinarily this fit will not be a press fit and the hand device can be used to pull the die out of the opening. The plug 8| may be turned so as to shift the pin 84 relative to the pin 16 since the pin 84 is eccentric to the plug BI, and this is desirable so as to enable adjusting the location of the pin 84 in the event the opening 15 in the die holder varies in location.

l. A device for pulling a die element or the' like out of a holder wherein the element has a die opening terminating at its inner end in a substantially radial, outwardly directed shoulder, comprising a shank adapted to be moved through the opening, a split resilient ring on the shank, and abutments at each axial end of the ring to press the ring through the die opening when the shank is moved into the opening and to pull the ring when the shank is moved reversely, said ring being substantially shorter in an axial direction than the distance between the abutments and being of such radial dimensions that it will resiliently contract when pressed into the die opening and being provided with a circumferentially extending rabbeted portion adapted to expand into engagement with said shoulder after sufficient movement of the ring through the openmg.

2. A device for pulling a die element or the like out of a holder wherein the element has a die opening and is held in a holder by a releasable lock accessible for release through an aperture in the holder adjacent the die, which comprises a shank having means on one end adapted to engage the die upon insertion of such end of the shank into the die opening, a plunger adapted to enter the aperture and release the lock, and adjustable means mounting the plunger on the shank so that the plunger may be variably positioned radially of the shank.

3. A device for pulling a die element or the like out of a holder wherein the element has a die opening terminating at its inner end in a substantially radial, outwardly directed shoulder, comprising a shank adapted to be moved through the opening, a radially expansible and contractible ring element on the shank, and abutments at each axial end of the element and spaced a distance greater than the axial length of the element to allow the latter to slide between the abutments, one of the abutments being adapted to press the element through the die opening when the shank is moved into the opening and the other abutment being adapted to pull the element when the shank is moved reversely, said element having a frusto-conical inner peripheral surface for engaging said other abutment so as to create expansion forces on the element.

4. A device for pulling a die element or the like out of a holder wherein the element has a die opening terminating at its inner end in a substantially radial, outwardly directed shoulder, comprising a shank adapted to be moved through the opening, a radially expansible and contractible ring element on the shank, and abutments at each axial end of the element and spaced a distance greater than the axial length of the element to allow the latter to slide between the abutments, one of the abutments being adapted to press the element through the die opening when the shank is moved into the opening and the other abutment being adapted to pull the element when the shank is moved reversely, said element having a frusto-conical inner peripheral surface and said other abutment having a frustoconical outer surface for engaging the inner surface 'on' tl e elei'ne'nt st as to create expansion forces on the element. 7

5. A device for pulling a die element or the like out of a holder wherein the element has a die opening terminating at itsinner end in a substantially radial, outwardly directed shoulder, comprising a shank adapted to be moved through the opening, a radially expansible and contractible ring element on the shank, and abutments at each axial-end of the element and spaced. a distance greater than the axial length of the element to allow the latter to slide between the abutments, one of the abutments being adapted to press the element through the die opening when the shank is moved into the opening and the other abutment being adapted to pull the element when the shank is moved reversely, said ring element having a frusto-conical outer surface converging towards said other abutment.

6. A device for pulling a die element or the like out of a holder wherein the element has a die opening terminating at its inner end in a substantially radial, outwardly directed shoulder, comprising a shank adapted to be moved through the opening, a radially expansible and co-ntractible ring element on the shank, and abutments at each axial end of the element and spaced a distance greater than the axial length of the element to allow the latter to slide between the abutments, one of the abutments being adapted to press the element through the die opening when the shank is moved into the opening and the other abutment being adapted to pull the element when the shank is moved reversely, said ring element having a frusto-conical outer surface converging towards said other abutment and a circumferentially extending rabbeted portion at the larger end of said surface to receive said shoulder upon expansion of the ring element.

7. A device for pulling a die element or the like out of a holder wherein the element has a die opening terminating at its inner end in a substantially radial, outwardly directed shoulder, comprising a shank adapted to be moved through the opening, a radially expansible and contractible ring element on the shank, and abutmenls at each axial end of the element and spaced a distance greater than the axial length of the element to allow the latter to slide between the abutments, one of the abutments being adapted to press the element through the die opening when the shank is moved into the opening and the other abutment being adapted to pull th element when the shank is moved reversely, said ring element having a frusto-conical outer surface decreasing in diameter towards said other abutment and a frustoconical inner surface increasing in diameter towards said other abutment.

8. A device for pulling a die element or the like out of a holder wherein the element has a die opening terminating at its inner end in a substantially radial, outwardly directed shoulder, comprising a shank adapted to be moved through the opening, a radially expansible and contractible ring element on the shank, and abutments at each axial end of the element and spaced a distance greater than the axial length of the element to allow the latter to slide between the abutments, one of the abutments being adapted to press the element through the die opening when the shank is moved into the opening and the other abutment being adapted to pull the element when the shank is moved reversely, said ring element having a frusto-conical outer surface decreasing in diameter towards said other abutment and a frusto-conical inner surface increasing in diameter towards said other abutment and the latter having a frusto-conical outer surface adapted to engage the inner conical surface of the ring element.

9. A device for pulling a die element or the like out of a holder wherein the element has a die opening which terminates inwardly in a surface of larger diameter to provide an annular shoulder, which comprises a shank insertable into the opening and having a circumferentially extending recess around the insertable end portion thereof, and a resilient split ring in said recess which is contractible to enter the opening and expansible after entering the opening to engage behind the shoulder, said ring having a frusto-conical inner peripheral surface increasing in diameter towards the insertable end of the ring and the recess having its side wall next to the insertable end of the shank shaped frusto-conically to substantially fit the inner surface of the ring, whereby reverse or Withdrawing movement of the shank tends to expand the ring, the outer peripheral surface of the ring being tapered axially towards its insertable end to facilitate insertion and simultaneous contraction of the ring.

ALBERT BOLDUC. 

